Stay hydrated on your outdoor adventures with the ingenious Aonijie Soft Flask 250ml Quick Stow. It features an adjustable mouthpiece for ease of use, dual caps design for efficiency, as well as a BPA-friendly PP cap. The antibacterial TPU is much safer to use than alternative materials and it comes in a convenient foldable format. Cap for bite valve (easily removed or replaced) Sliding bite valve lock 360-degree rotation TPU Antibacterial construction Frost and high temperature resistant Easy to clean Capacity: 500ml Frost and temperature resistance: 0°C to 40°C